Escapement mechanism for type-writing machines.



E. G. LATTA. E$GAPEMENT MECHANISM FOR TYPE WRITING MACHINES.

APPLIUATION FILED JULY 6, 1905. 944,794, Patented Dec. 28, 1909. I 2SHEETS-SHEET 1.

. ummliiiimrr 7 WWI I INVAENTUR' v4 7' THRIVE K E.G.LATTA. ESGAPEMENTMECHANISM FOR TYPE WRITING MACHINES.

APPLICATION FILED JULY 6, 1305.

944,794. Patented Dec.28, 1909.

' 2 SHEETS-SHEET 2.

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EMMIT- e. LATTA, or SYRACUSE, NEW YoBK;

ESGAPEMENT MECHANISM FOR TYPE-WRITING MACHINES.

Specification of Letters Patent.

7 Application. filed July 6, 1905.

Serial No: 268,565 J To all whom it mayconcem:

Be it known that I, EMMrr G. LAT'rA, of syracusaoin'the county ofUnondaga, in the State of N ew York, have invented new and usefulImprovements in Escapement Mechanism for Type-Writing Machines, of whichthe following, taken in connection with the accompanying drawings, is afull, clear, and exact description.

This inv ention relates-'to improvements in typewriting machines andrefers more particularly controlling the movement of the carriage.

. .My object is to produce an escapement mechanisrnwith asfew parts aspracticable, thereby eliminating some of the elements with the resultthat certain defects, due to the presence of those elements, are doneThlS escapement mechanism is mounted,

in its action away with and the mechanism is made lighter in weight,more positive and rapid and enables the carriage to be moved backwardand forward.

Another object is tomount the star-Wheel and its pinion u on specificadjustable bearings which are ust-proof and capable of re, taming 'alimited quantity of oil for the. lubrication of the bearings andtootherwise arrange said parts as to insure a free and easy action ofthe moving elements,

upon a fixed support. upon the frame of the machine and I have,therefore, shown only the bare escapement mechanism and a "very smallportion of the fixed supports therefor together with a small rack whichmeshes wit the pinion.

In the drawings-1*" igure 1' is a topplan of my improved escapementmechanism and the. adjacent. portions of the supporting fra'mefandtoothed rack ofthe carriage. F igs. 2 and3 are sectional Views taken resectively on lines 2--2, and 33, Fig. 1,

ig.-2 showing the 'star-wheel and escapement-pawl'in end view, and Fig.3 showing the same parts,'together with-their bearin s in section.-Figs. 4 and. 5 ar'erespective y top plan and side elevation of a portionof and lever in the supportin frame upon which the/es capement mecanis'm is mounted, Figs. 6, 7 8, and 9 re resent the escapement wheel, eevation on an enlarged scale, and show those parts in some of thedifferent positions they assume when in operation.

The mechanism involved in my resent invent on comprises essentially,porting frame -o1- opposed bearings 2 to the escapementmechanism. for

mounted upon a pivotal pin l2 ortion of the toothed and -3 a star-wheel4 and pinion -5 which are mounted to rotate in said.

bearings, an escap'ement-pawl -6- co-acting with the star-wheel 4 andatoo'the'd rack -i-7- which may be mounted in any suitable manner uponany form of carriage, not necessary to herein illustrate or describe, asthe action of the rackand pinion, in controlling the movement of thecarriage, is well understood. l I

Theyoke, orsupport l is fixed to and may forma part of the main frame ofthe machine, and in this instance consists of a rectal bar havin aportion thereof enlarged and formed wit 1 a central vertical opening 8'therethrough for the reception and play of the star-wheel'4 and itspinion -6 so that. the pawl or lever 6 is sub stantially balanced uponthe pivotal pin The bushings 2 and 3 are screu d into their respectiveapertures from the outer faces of the yoke 1 and are each providedatthen inner ends with an annu-,

a-r ball-race -13 and inwardly projecting annular flanges -1et forforming oil cups or pockets -15',in which suitable-balls 16 are seatedand ride upon or against the annular raceways"13, the annular flanges-.14- projecting a suflicient distance inwardly beyond the ball-bearings13- to retain a limited quantity of oil in the recesses l 5-.

ing 2: which is at the inner or front 'side of the yoke -1 andstar-wheel-4- is enlarged for forming an annular fiahge -17abutt1ngagainst the adjacent face of the 'yoke when the bushing Q is screwed uptight-1y. The other bushing --3 on the rear side of-the yoke 1- isadjustable axially and concentric with the Patented Dec. 1909.

The outerend of the bush-.

. protect the bearings against the entrance of axis of the star-wheel &-and bushing 2' and is held in its adjusted position-by alock-nut l8engaging the outer threaded end of the bushing -3- and abutting againstthe adjacent face of the yoke l,. It will be observed that theilever- 6is centrally pivotedupo'n the pin 12 directly below (on in any othersuitable circumferentialpos tlon) the star-wheel -4.- and therefore, ltSopposite ends-or armsextend substantially equidistant in oppositedirections from its pivot and lie in substantially the same plane assaid star-wheel, so that by rocking the lever its opposite endsintersectthe path of movement of the points of'the teeth of thestar-wheel. v

The eseapement-wheel fl and pinion are centrally mounted upona hollowspindle or shaft 20vhaving cone-ends or bearings 21 entering the.op'eninner ends of the cups and restingon theballs 13 within theannularflanges 14, which latter have a-running'fit with the shaft or spindle todust and other'foreign matter. The 'p'inion '5 is preferably integralwith its supporting shaft to secure perfect concentricity. an

,alinement and is formedwith-a radial 'oilpassage 22 communicating witha central. lengthwise oil-passage 22 through the shaft,

the radialpassage 22 being located at one side of the rack -.-'7, whereit is accessible for the introduction of a lubricant when needed,and-when so introduced readily finds its way through the passage 22'into the cups 15. The es'capement-wheel 4, which is preferablyformed ofsheet metal, has a central threaded opening and is screwed tightly Iupon a left-pitch thread 23 onthe shaft ra ck meshing with the pinion -5tends to rotate the star-wheel 4' in one direction andagainst theadjacent end face of the pin- 1on 5 so that the shaft, pinion and escapement wheel 'form practicallyaunitary rev'o-- luble; structure. A

It is, of course, understood that in almost "all standard typew'ritingmachines the carriage and toothedrack mounted thereon are lrawn in onedirection by suitable spring motor,but it IS believed to be unnecessaryto show any additional parts of the carriage, or its actuatingmechanismother than the toothed bar which meshes with the pinion It is nowobvious that thetoothed indicated by arrow -.r-,.Fig. 2, and the advancefaces or edges of the teeth facing in,

the direction of such rotation are disposed substantially radial whilethe other edges are tangential toa circle within the peripheryandccncentric with the axis of the starwheel." Inithe furtherdescription of these teeth these edgcswill betermed respectively, radialand inclined or beveled. The-lever 6 isjaccordingly constructed toengage with both the radial and. inclined edges of against furthermovement. repeated with each movement of any one ot:

\ inclined face the teeth, one of its arms extending in the direction ofautomatic rotation of the star- .wheel,,being hook-shaped and formedwith a shoulder which is radial with the star-wheel and is also formedwith anaddithe shoulder 25 and angle -29 lies in close proximity to thepoints of the teeth and embraces a number of said teeth, but are sorelatively arranged that when the shoulder 25 is in holding engagementwith oneof the radial edges of one of the teeth the other point 9.9 liesbetween radial lines drawn through the points of two adjacent teeth atthe opposite side of the pivot 12 from the shoulder 25 and just outsideof the lineof travel of the points of-the teeth. Fig. 6 represents thewheel l and -lever 6 .in the same position as in Fig.

2, whichis the normal or locking position of the lever, thisshows thatif the end of the lever having the part 29 be raised to the positionshown in Fig. the tooth 'bwill be free from the detent 25-, and that thewheel actuated by the power driven pin ion 5 "will instantly moveforward until the tooth contacts with the inclined face --27- and forcesthe lever back to its normal. position when the detent will interceptthe tooth --c"- and lock the wheel This action is the type-bars, or ofthe space key, and it should. be noted that the wheel moves one wholeletter space, or the distance from one tooth to another without theusual intermediate-stop; thi for the reason that the -27- does notobstruct the movement of the wheel. The only functionof the inclinedface 27- is to cause the V wheel-to positively return the detent +25 toits locking position as the tooth f forces the inclined face '-27--' outof its way. The lever -6'- is actuated by a re ciprocating rod 30-, andthis in turn is thrown upwardly by any kind of a. universal bar thatwill transmit-a sudden impulse to the rod at the instantthe type barsstrike the platen and then retreat. a short distance before the keylevers start back toward their normal position, or a universal baradapted to act on the rod-by momentum after the universal bar has passedbeyond the control of the key levers; as such universal bars are wellknown in the art, and form 116 part of my present invention, theirfurther description is omitted. The rod 30 is support ed by a bracket 32fixed to the frame of the machine, and slides in an aperture 31 therein,the rod as shown in Fig. 2 is made to push upwardly against the lever.6, but is. not pivotallyconnected thereto.

The lever 6-- 1s held in its normal position by a spring connected'tothe lever at one side of its pivot and its other end'connected to anadjustable lever" as. before "described.

anchorage -3tf which is rigidly supported by the frame of the. machine,the chief fnnction of this spring is to hold the lever in its normalposition, but incidentally it acts to assist-i the wheel in returningthe lever. to its normal position; this is a useless function for thereason that the wheel automatically, and positively returns the n Thespring 32" must be of only sufficientpower; to hold the lever 6 againstvibration at the instant between the time when the. tooth.

f leaves the inclined face --27 and the engagement of tooth 0- withthede tent -25-', this because, if a spring more than slightly strongerthan required be used, it would in the case of a heavy, or sluggishcarriage,- return the lever to its locking position before the carriagedriving lTlOVQlllGIlt- VVhtlilthen cause the tooth 'dto contact with theinclined face 2.8 of the lever and .lever simply vibrates on force itout of the'way as shown in Fig. 9' and at the same time restore the face'26- to a position to beacted on by the next tooth of the wheel. From;this it is seen that the its pivot as the wheel is turned. backwardly,and that the carriage may be set back any distance from a single spaceto the full length of its rack bar, and that in all cases the detentwill in- "terlock with the last tooth that may have passed itduring-such backward movement of the carriage, as soonas the carriage isre store'dto the control of thedriving spring. It should be understoodthat during the backward movement of the wheel the lever vibrates freelywithout movement of the rod -30, and the only noise is that'made by thelever as' it vibrates against the teeth of the wheel, and this is soslight that a sep- 32-- which has one end" and but little thuspreventing &

arate ratchet and pawl is not required to preventaction of the lever andwheel. v

This escapement mechanism comprises but two Working parts viz; the wheel-4 and lever -6- both of which arev particularly light and easy ofaction, and therefore respond' quickly to the action of'their respectiveoperating devices, as the rack and pin ion -7- and The wheel -&-- andthe lever 6 are both made of sheet metal. and are thereforecomparatively inexpensive to manufacture, and as both are arranged inthe same plane,

on parallel pivots, there is no end thrust on the pivots, and thefriction and wear is greatly reduced as comparediwith 'esca ementshaving beveled working faces th at necessitate their pivots beingarranged on different angles.

" The detent -2G- is made with-its face atsubstan'tially right angles toa line drawn between the axes of the lever -6- and wheel 4--,' and itmeets the back face of the teeth of the wheel on this angle so thatthere is no tendency for the tooth to slip, power is required to trlpthe detent; the teeth of the wheel may be-made 1 at entangle not radialand the lever pivot arobtained. The anglesof the'inclined faces somewhatand thegsame result'be obtained, furtheruse and eXpernnen-tis requiredto decide Just what form thesefaces'should be toobtain the best results.I I am aware that a two part escapement has been .made in which onepart'of the lever has been arranged "with two holding detents in away tostopthe'wheeltwice for each letter space,-also'that'it is old to arrangethe holding dogs in a way to be returned to their normal positicn'by thewheel, first to produce in :a

but I believe I am the typewriting machine a in which. a rigid one partvibrating lever operates when tripped to permit the wheel te move acomplete lctt er space, and in which the Wheel positivelycreturnsthelever to its locking position. I also believe I am: first to arrangean escapement consisting of but two working'parts, a lever and wheel, ina way to cause the wheel to move forwardly with an intermittent rotarymotion when the lever is vibrated, and to permit the lever to vibratefreely as the wheel is turned backwardly with a'constant rotary motion.

What Iclaim is:

1. In a typewriti-ng machine, an escapenient mechanism comprising apower driven toothed wheel anda key operated lever pivoted intermediateits ends, which latter are movablealternately into and out of the path 7of the points of said teeth, one ofisaid ends constituting a detenttonormally lock the wheel against forward rotation, and the ranged tocorrespond andthe same, result two part escapementdriven escapementWheel with a centrally pivoted p votfor the leverbeing arranged on aline on the release of the key operated means.

against forward movement, and an inclined.

yieldingly hold the detent in said position,

.d etent for stopping the wheel at one end and r v the radial line ofthe tooth in contact.

'ing detent for tha wheel with means for other end comprising means bywhich said" wheel cams the lever to its normal position 2; In atypewritingtmachine, a power driven es'capement wheel, in combinationwith a centrally pivoted'lever having a de: tent at one end normallylocking the wheel against forward movement, and an inclined part on itsother end on, which the escapement wheel acts to restore the detent tolocking position each time the lever is vibrated to unlock the wheel, aspring acting to hold the detent in'its normal position, and means torock the lever against the action of said spring.

3.111 a typewriting machine, a power in combination lever arranged atone side of the wheeland'having a detent at one end normally locking thewheel part on its other end on which the escapement wheel acts torestore the detent to lockingposition each time the lever is vibrated:to unlock the wheel, aspring to and manually operated means independentwheel for vibrating the lever to release, the wheel from the detent.

"4. In a typewriting machine, a power driven escapement wheel havingteeth with their working faces on radialt'lines, in combination with acentrally pivoted lever arranged in the plane of the wheel having aanyinclined surface to intercept without stamping-the wheel at the otherend, the

elxtendiiigirom the point of contact between the detent and wheel and atright anglesto 5. An escapement mechanism for typewriting' machines,-comprising apower driven toothed wheel, and a centrally'pivoted leverrigidly connecting 'a locking detent for the wheel at one side of itspivot and a non-holding inclined face at the other side of said pivot,with means for tripping the lever to unlock the detent and at the sametime interpose the inclined face between the teeth of thewheel,'thewheel acting with its first forward movement to move the inclined faceout of its path and restore the detent to its locking position.

6. An escapement mechanism for typewriting machines, comprising a powerdriven tfobthedwheel, and a one piece centrally pivoted lever forming asingle locktripping the lever to unlock the detent, the leverjbeingarranged t6 permit the wheel to move without stopping a distance equal,to I writing machines,

the space between two of its teeth each time the lever is tripped, andto be actedon by the wheel during itsforward movement to restore thedetent to its locking position.

7. In a typewriting machine, an'escapement wheel, and a pinion by whichit is driven, in' combination with a hollow shaft having an supportingthewheel and pinion, with oppos'ed caps having recesses and ballstherein to support the cones, the inner faces of. the cups beingextended to overhang the balls and rest in close relation to the coneswhereby the ciipsretain oil, and exclude-dust.

8. In an eseapement mechanism for typewriting machines, a power driventoothed wheel, and a vibrating centrally pivoted leoil inlet and a coneat' each end ver arranged in substantially the same plane 1 as the wheelhaving a detent (in-one end act'- ing to lock the wheel againstforwardrotation, vand an interceptingnon-locking projection on the otherend, said detent and intercepting projection beingarranged toperstopping. Y

j 9. In anescapement mechanlsm for typewriting machines, a power driventoothed wheel, and a centrally pivoted vibrating-lever supporting adetent for locking the wheel against forward rotation at one side of itspivot and an intercepting non-locking projection at the other side ofsaid pivot, with means for tripping the lever, the lever being arrangedhavingits pivot locatedzin close relation to the outer edge of the wheelandin substan tially the same plane.

10. In an escapement mechanism for typea power driven toothed wheel anda'centrally pivoted vibra'tinglever arranged on one side of the wheeland in substantially the same plane having a detenton one end forlocking the wheel against forward rotation and an interceptingprojection on the other end, with means for'tripping the lever,saiddetent and intercepting projection vibrating alternately toward thewheel from points substantially the same distance from the wheel as thelever pivot and said wheel being adapted to move forward one whole toothspace each time the lever is tripped and to act on the interceptingprojection during such move ment to restore the detent to locking posi-Witnesses 2 HAnvnY A. Moran, FRAN E. REID. I

on one side of the wheel and] In testimony whereof I have hereunto setmit the wheel to rotate backwardly without

